Mistral Medium 3.5 Becomes Le Chat Default and Powers Unified 'Vibe' Agent for Work and Code

Mistral (via Releasebot)·medium signal

Mistral's Medium 3.5 scores 77.6% on SWE-Bench Verified with strong agentic capability (91.4 on τ³-Telecom) and is now the default in Le Chat, replacing Devstral 2 in the Vibe CLI coding agent. Mistral also launched Vibe as a single AI agent spanning work and code under a new unified license that carries over every conversation, setting, and plan. Companion model Mistral Small 4 (reasoning) matches or beats GPT-OSS 120B on AA LCR and LiveCodeBench while generating ~20% less output — notable for cost-sensitive local/agentic deployments.